0
\$\begingroup\$

I am trying to work out a simulation circuit with different nmos(2n7000) and pmos(ZVP2106A) within LTspice.

But I just don't know what to do to make the simulation run. I've taken careful procedures to make sure that the text file was downloaded in the same directory as my schematic and added the spice directives

.lib 2n7000M1.txt, .lib 2n7000M2.txt, .lib ZVP2106A.txt,

And once ran the error shown

m1: Can't find definition of model "2n7000m2"

This error popped for all nmos and pmos.

enter image description here

enter image description here

As shown, the first image shows what schematic I'm trying to run a simulation for with the imported pmos and nmos. For the other image shows proof that they are in the same directory. The schematic is named

Test1 and the text fileS that I was trying to import are labels "2n7000M1, 2n7000M2, ZVP2106A".

I've tried putting an X for the prefix to try make it a sub circuit but got the error

Unknown sub circuit called in: xm2......

I'm stuck and in need for help. I've already mention the problem with my professor. So I decided to hit the web for answers/solutions regarding the problem. Any help is welcome and much appreciated.

Thank you!

\$\endgroup\$
2
  • 2
    \$\begingroup\$ If you're going to use the default location it needs to be Documents\LTspiceXVII\lib\sub, and not Documents\LTspiceXVII\lib. i.e. you're one directory too high. \$\endgroup\$
    – Ste Kulov
    Mar 19, 2021 at 5:01
  • \$\begingroup\$ Please be careful with making IC structures, such as current mirrors, using 3-terminal discrete MOSFETs. You need to use the 4-terminal monolithic ones with explicit body connections (nmos4 and pmos4) and tie the pmos bodies to Vdd and nmos bodies to Vss. \$\endgroup\$
    – Ste Kulov
    Mar 19, 2021 at 5:02

1 Answer 1

1
\$\begingroup\$

Go to Tools -> Control Panel -> Sym and Lib Search paths Then add you path for you lib/txt files (just in case your path seems like the default one so may not be needed)

For windows press CTRL + Right Click on mosfet parts. Then change prefix to "X".

menu options

For clarification see tested circuit below example

\$\endgroup\$
1
  • \$\begingroup\$ For future viewers, the Value needs to match the name in the file. The name follows the top statement in file either .MODEL or .SUBCKT \$\endgroup\$
    – Ernesto
    Mar 19, 2021 at 16:46

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.